Effects of Nd substitution on magnetic and magneto-optical properties of TbCo/Cr films

Abstract

NdTbCo/Cr amorphous films with high perpendicular magnetic anisotropy were prepared onto glass substrates by rf magnetron sputtering. The effects of Nd substitution on the magnetic and magneto-optical properties of TbCo/Cr films were investigated. It was found that partial Tb substitution by Nd would increase the saturation magnetization and the Kerr rotation angle, change the temperature dependence of magneto-optical characteristics. These results can be explained by the ferrimagnetic structure of the rare earth-transition metal alloy. When the magnetic layer composition was (Nd_0.265Tb_0.735)₃₁Co₆₉, a saturation magnetization of 247 emu/cm³ and a coercivity of 3.8 kOe at room temperature could be obtained.

Keywords

NdTbCo/Cr films / perpendicular magnetic anisotropy / saturation magnetization / Kerr rotation angle / ferrimagnetic structure

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